Device for actuating electrical switches



Dec- 9, 1952 E. GRETENER DEVICE FOR ACTUATING ELECTRICAL SWITCHES FiledSept. 27, 1950 .D E m, F

INVENTOR.

A'ITORNEYJ.

Patented Dec. 9, 1952 OFFICE DEVICE FOR ACTUATING ELECTRICAL SWTCHE'SEdgar Gretener, Zurich, Switzerland Application September 27, 1950,SerialNo. 186,998 In Switzerland October 3, 1949 (Cl. 20G-18) 11 Claims.

The present invention relates to a device for actuating an electricalswitch or switch unit according to a prearranged program. Such devicesthat have become known are widely employed in the art of automaticcontrol and regulation where the control serves e. g. to put into or outof action in preselected time relation the different mechanisms requiredto carry out the necessary sequence of steps of anautomatica-llycontrolled process. Another very interestingxeld ofvapplication is the technique of telecommunication where it is theobject of such devices to form current impulses of a prescribedsequence. Such` control systems are generally referred to as programcontrols and the sequence -of eiects brought about by such systems isusually referred to by the term program The vobject of the presentinvention is to provide a device foractuating at least one electricalswitch according to a predetermined program which may be varied in avery easy and simple manner.

It is another object of the present invention to provide a device foractuatingA simultaneously two switches, each according to oneof twopredetermined programs, which programs may be set entirely independentofV one another.

It is furthermore an object ofv this invention to provide a device foractuating switches according to a predetermined program. permittingclear indication of` the. position of the switch actuating means.

Another important object of, the, invention is to provide means for aneasy assembly of the switch actuating means on said device.

The foregoing objectsv are. preferably achieved by the employment of adisc with at least one row of slotted heads disposed turnably along thecircumference of said disc in combination with at least onefeeler springadjacent lto said row of slotted heads, where said disc is rotated insteps locating consecutively each slotted head beneath the end of saidfeelerspring, and Where the feeler spring actuates said electricalcortact according to the position of said slotted head', and where theslot ofeach slotted head may be set to two definite and securedpositions alternatively, and where in one of said positions the contactis actuated and where` in the other one the contact is not actuated.

vThese and other features willy become evident andthe invention will bebest understood from the following detailed description made withreference to the accompanying drawings representing embodiments of theinvention, where Figs. la and 1b by ways of example show in front andside elevation a disc with one row of slotted heads, and

Figs. 2a, 2b and 2c show a disc with a double row of slotted heads, Fig.2a representing a section along the axis of the disc, Fig. 2b a sectionof the embodiment along plane A--A of Fig. 2a, and Fig. 2c a developmentview showing the arrangement of slotted heads along the circumference ofthe disc.

In Figs. 1a and 1b I represents a disc along the circumference of whicha multitude of slotted heads is arranged in one row, three of which areshown. 3I and 33 are disposed with slots parallel to the axis oi thedisc. The slot of head 32 is in a position tangentvto the circumferenceof the disc in that particular point. Hereinafter the position of heads3| and 33 will be referred to as axial, the position of head' 32 astangential. The employment of such two positions seems particularlyadvantageous, although any two other distinctly distinguishablepositions may be employed. The slotted head disc I serves to operate aswitch unit 4. This is elected in the embodiment shown by a testingspring Erproviding a stud 6 and a bent end I2 which latter may enterinto the slot of the adajcent head if it is in axial position. The spoton the circumference of disc I which is located beneathv the bent end I2 is referred to hereinafter as the scanning spot. An auxiliary lever 'Irotatable around its axis 8 is urged downward by a spring 9 against acam wheel It. Said cam wheel is coaxially attached f to the slotted headdisc I and provides a number of rises 35 equal to the number of slottedheads on disc I. By the rises 35 on cam wheel ID the bent end II oflever 'I is actuated.

The embodiment operates as follows: The position of spring 5 isdetermined by the position of the slot of that head of the disc I whichis at that given moment located at the scanning spot, i. e. beneath thebent end I2 of the spring. If the slot is in tangential position, e. g.as head 32, the bent end is stopped by the edges of the slot. As thebent end cannot enter into the slot, the switch unit 4 remains closed,contact leaf spring being held upwards by the stud 6. If, however, e. g.the head 3| or 33 would be located underneath the bent end I2, this canenter into the slot, as the slots of such heads are in axial position,i. e. parallel to the bent end I2 of spring 5. In this position of thedisc the switch 4 is opened.

The slotted heads are consecutive-ly located In the drawing the slottedheads tions. fiat arms 23 of two disc springs 3G, slotted acbeneath thebent end l2 preferably by a step-bystep rotation of the disc. Thus headafter head is brought into the testing position. During the intervals oftransport, the spring 5 must be lifted so far as to permit free movementof the disc unrestricted by the end I2 of the spring. This may beachieved in different ways. In the embodiment of Fig. la the cam wheelIB and the auxiliary lever 'I serve for this purpose. During theintervals of transport the lever 'i is tilted counterclockwise. Therebyspring 5 is deflected upwards, so that the transport movements may beexecuted without interference by that spring. The shape of the cams andtheir position on the circumference of the cam wheel must match with theposition of the heads on disc l in such a manner that the bent end I2 islifted out of the slot of the adjacent head before it can strike theedge of the slot.

A further embodiment of a slotted head disc is shown in Figs. 2a to 2c.On the disc shown two circular rows of slotted heads are disposedsymmetrically to the plane of the disc. With such an embodiment twoseparate switch units may be actuated independently of one another bythe slotted heads of the two rows on both sides of the disc.

. part 2| adjoining to said circular part 2@ of the peg serves to securethe position of the slot in one of the above mentioned two denite posi-This is effectively achieved by separate cordng to the number of pegs,which press with equal tension against opposite sides of the squareprismatic part of each peg.

Such an arrangement of the fiat separate arms of the .disc springs oneach side of each peg v eliminates superfluous friction in the supportof the pegs. Besides the shown construction provides the advantage thatthe slotted heads may be rotated in both senses and no restrictionsexist as to the sense of rotation and to the number of successiverotations.

A circular cone 2li at the bottom end of every peg permits very easyassembly of the pegs into the disc l as the pegs have only to beinserted into the holes of the .disc and presseddownwards.

rIhe circular base of such cones protrudes from the square part of thepeg as may be seen from the drawing. Thereby a very simple method isprovided to secure the pegs against falling out as the fiat arms of thedisc spring 3@ embrace the cone. With regard to an easy manufacture thebase of the circular cone is made equal in diameter to the cylindricalpart of the peg. Thus the square prismatic part may be easily machinedout of the cylindrical part originallyY reaching up to the conical end.

To permit quick and easy setting or resetting of a given program it isof pre-dominant importance that the position of the slots is easilydistinguishable. For this purpose narrow coloured strips are painted onthe bottom of each slot. The colour of such strips must form adistinctly discernible contrast to the colour of the bottom, e. g. whiteon black. In order to protect the coloured strips against damaging by atool eventually employed for setting the heads, e. g. a special screwdriver, the coloured strips are located in a recess at vthe bottom ofthe slot.

It is furthermore required that no slotted head of the disc mustinadvertently be turned when setting the adjacent heads. In order toachieve this the heads themselves are recessed with respect to thecircumference of the disc as is shown in Figs. 2a and 2c.

The slotted heads on the left side of the embodiment shown in Fig. 2aare mounted in recesses so that they are iiush with the circumference ofthe disc. Thus the slot is closed at both sides in the radial positionas well as in the tangential one. In the axial position, which permitsthe bent end of the feeler spring 5 to enter into the slot, this is notvery convenient with regard to the ytolerances of manufacture. Feelerspring 5 ought to be made as broad as possible in order that it may bearrested securely at both ends by the edges of the slot, if it is intangential position.V On the other hand a sufficiently large clearancemust be provided on both sides of the end of the spring to warrant safeentering into the slot if it is in axial position.

The design shown at the right side of the embodiment of Fig. 2aV meetswith both requirements as the slot is left open towards the flange ofthe disc if it is in axial position. By simply turning 01T the ange ofsaid disc by a small amount, indicated at 2l, the cylindrical recessinto which the slotted head is mounted leaves open a small gap 28.Thereby the above mentioned requirements are considerably simplified andthe admissible tolerances for manufacture are increased.

The slotted heads may be numbered, e. g. 46 and 47 as shown in Fig. 2crepresenting a developed view of a part of the circumference of thedisc, in order to facilitate the setting of a program. The numerals arepreferably applied to the disc on a separate track in between the tworows of slotted heads.

Iclaim:

1. A device for actuating an electrical switch according to apredetermined program, the switch having two alternative end positions,said device comprising a disc supported for step-bystep movement, a rowof slotted elements turnably disposed along the circumference of thedisc, a feeler element constituting a switch operator and having afeeler portion positioned to contact said slotted elements in sequenceon a step-bystep advance of said disc, and means for retaining theseveral turnable elements each in adjusted relation on said disc withthe slot thereof in position to be entered by the feeler portion of saidfeeler element or alternatively in position to block entry thereof bythe feeler portion, whereby the switch is actuated to one or the otherof its alternative end positions in accordance with the adjustment ofthe feeler element as determined by the position of the slot of theturnable element contacted by the feeler element.

2. A device according to claim 1, where said turnable elements haveslotted heads mounted in recesses along the circumference of said disc.

3. A device according to claim 2, wherein one of said positions the slotis disposed parallel to the axis of said disc, and where in the otherone said slot is at right angles to the axis of the disc and disposed ina plane tangential to the circumference of the disc.

4. A device according to claim 3, where a rim of the disc is providedwith lateral openings in elongation of said slots when in axialposition.

5. A device according to claim 4 where said rim of the disc is ofreduced diameter to leave open the adjacent edges of said disc recessesin which said slotted heads of the turnable members are mounted.

6. A device according to claim 2, where the position of the slot ismarked by a colored strip at the bottom of the slot and where the colorof said strip forms a distinctly visible contrast to the color of thebottom of the slot.

7. A device according to claim 6, where said colored strip is located ina recess at the bottom of each slot, whereby protection againstmechanical damaging thereof by said feeler portion of said feelerelement is obtained.

8. A device according to claim 1, where two rows of slotted elements aredisposed symmetrically to the plane of said disc, and a feeler elementis provided for each row of slotted elements, whereby two separatelyoperating devices are obtained.

9. A device according to claim 1, where each of said slotted elementscomprises a peg having a cylindrical slotted head for mounting said pegrotatably on said disc, an adjoining square prismatic part cooperatingwith said retaining means to secure the peg in adjustment for thedesired position of the slot, and a circular conical part to facilitatethe assembly of pegs on said disc.

10. A device according to claim 9, where for a row of slotted heads twodisc springs are employed concentrically mounted on said disc andslotted according to the number of pegs, and where the position of theslot on said pegs is secured by the separate flat arms of said discspressing from both sides against opposite sides of the square prismaticpart of the pegs.

11. A device according to claim 10, where the base of said conical partof the pegs is equal in diameter to said cylindrical part and where thesurfaces of said square prismatic part in crosssection chords of thecylindrical portions of said pegs, whereby the pegs are secured by saiddisc springs against falling out.

EDGAR GRETENER.

REFERENCES CITED UNITED STATES PATENTS Name Date Babajoi Nov. 1, 1949Number

